Find research datasets worth reusing

Fig. 5 in Protomelas krampus, a new paedophagous cichlid from Lake Malawi (Teleostei, Cichlidae)

Fig. 5. Photograph of preserved paratype (RMCA 99-041-P-4767) of Protomelas krampus sp. nov., shortly after preservation.

Fig. 4 in Protomelas krampus, a new paedophagous cichlid from Lake Malawi (Teleostei, Cichlidae)

Fig. 4. Photographs of preserved specimens of Protomelas krampus sp. nov. A. Holotype (RMCA 99- 041-P-4768). B. Paratype (RMCA 99-041-P-4767). Melanin pattern strongly faded.

Fig. 2 in Protomelas krampus, a new paedophagous cichlid from Lake Malawi (Teleostei, Cichlidae)

Fig. 2. Scatter plot of PC 1 against PC 3 for a principal component analysis of 21 log-transformed measurements of Protomelas krampus sp. nov., Caprichromis liemi (McKaye & Mackenzie, 1982) and C. orthognathus (Trewavas, 1935) (n = 12). P. krampus sp. nov. = blue dot; C. liemi = light brown dash; C. orthognathus = dark brown rectangle.

Fig. 1 in Protomelas krampus, a new paedophagous cichlid from Lake Malawi (Teleostei, Cichlidae)

Fig. 1. Scatter plot of PC 1 against PC 2 for a principal component analysis of 21 log-transformed measurements of all specimens studied (n = 44). Protomelas krampus sp. nov. = blue dot; Hemitaeniochromis brachyrhynchus Oliver, 2012 = purple square; H. urotaenia (Regan, 1922) = green square; Hemitaeniochromis sp. 'insignis like' = red triangle; P. spilopterus (Trewavas, 1935) = grey inverted triangle; P. insignis (Trewavas, 1935) = golden diamond; Caprichromis liemi (McKaye & Mackenzie, 1982) = light brown dash; C. orthognathus (Trewavas, 1935) = dark brown rectangle.

Fig. 7 in Protomelas krampus, a new paedophagous cichlid from Lake Malawi (Teleostei, Cichlidae)

Fig. 7. Distribution map of Protomelas krampus sp. nov. Red star = holotype; red dot = paratype; green triangles = possible sightings by Konings (2016); orange square = possible sighting by McKaye & Kocher (1983); yellow diamond = possible sighting by Stauffer (pers. comm.). Inset: map of Africa with indication of area of Lake Malawi.

Fig. 6 in Protomelas krampus, a new paedophagous cichlid from Lake Malawi (Teleostei, Cichlidae)

Fig. 6. Photograph of live specimen of Protomelas krampus sp. nov. (specimen not preserved; length unknown) (copyright Ad Konings).

opencc-zeroDec 2016View details →

Data from: Determination of the genetic architecture underlying short wavelength sensitivity in Lake Malawi cichlids

African cichlids are an exemplary system to study organismal diversity and rapid speciation. Species differ in external morphology including jaw shape and body coloration, but also differ in sensory systems including vision. All cichlids have 7 cone opsin genes with species differing broadly in which opsins are expressed. The differential opsin expression results in closely related species with substantial differences in spectral sensitivity of their photoreceptors. In this work, we take a first step in determining the genetic basis of opsin expression in cichlids. Using a second generation cross between 2 species with different opsin expression patterns, we make a conservative estimate that short wavelength opsin expression is regulated by a few loci. Genetic mapping in 96 F2 hybrids provides clear evidence of a cis-regulatory region for SWS1 opsin that explains 34% of the variation in expression between the 2 species. Additionally, in situ hybridization has shown that SWS1 and SWS2B opsins are coexpressed in individual single cones in the retinas of F2 progeny. Results from this work will contribute to a better understanding of the genetic architecture underlying opsin expression. This knowledge will help answer long-standing questions about the evolutionary processes fundamental to opsin expression variation and how this contributes to adaptive cichlid divergence.

opencc-zeroDec 2011View details →

Data from: Mitochondrial genome primers for Lake Malawi cichlids

Resolving the evolutionary history of rapidly diversifying lineages like the Lake Malawi Cichlid Flock demands powerful phylogenetic tools. Although this clade of over 500 species of fish likely diversified in less than two million years, the availability of extensive sequence data sets, such as complete mitochondrial genomes, could help resolve evolutionary patterns in this group. Using a large number of newly developed primers, we generated whole mitochondrial genome sequences for 14 Lake Malawi cichlids. We compared sequence divergence across protein-coding regions of the mitochondrial genome and also compared divergence in the mitochondrial loci to divergence at two nuclear protein-coding loci, Mitfb and Dlx2. Despite the widespread sharing of haplotypes of identical sequences at individual loci, the combined use of all protein-coding mitochondrial loci provided a bifurcating phylogenetic hypothesis for the exemplars of major lineages within the Lake Malawi cichlid radiation. The primers presented here could have substantial utility for evolutionary analyses of mitochondrial evolution and hybridization within this diverse clade.

opencc-zeroDec 2016View details →

Data from: Evolutionary divergence in life history traits among populations of the Lake Malawi cichlid fish Astatotilapia calliptera

During the early stages of adaptive radiation, populations diverge in life history traits such as egg size and growth rates, in addition to eco-morphological and behavioral characteristics. However, there are few studies of life history divergence within ongoing adaptive radiations. Here, we studied Astatotilapia calliptera, a maternal mouthbrooding cichlid fish within the Lake Malawi haplochromine radiation. This species occupies a rich diversity of habitats, including the main body of Lake Malawi, as well as peripheral rivers and shallow lakes. We used common garden experiments to test for life history divergence among populations, focussing on clutch size, duration of incubation, egg mass, offspring size, and growth rates. In a first experiment, we found significant differences among populations in average clutch size and egg mass, and larger clutches were associated with smaller eggs. In a second experiment, we found significant differences among populations in brood size, duration of incubation, juvenile length when released, and growth rates. Larger broods were associated with smaller juveniles when released and shorter incubation times. Although juvenile growth rates differed between populations, these were not strongly related to initial size on release. Overall, differences in life history characters among populations were not predicted by major habitat classifications (Lake Malawi or peripheral habitats) or population genetic divergence (microsatellite-based FST). We suggest that the observed patterns are consistent with local selective forces driving the observed patterns of trait divergence. The results provide strong evidence of evolutionary divergence and covariance of life history traits among populations within a radiating cichlid species, highlighting opportunities for further work to identify the processes driving the observed divergence.

opencc-zeroDec 2018View details →

Data from: A population genetic assessment of taxonomic species: the case of Lake Malawi cichlid fishes

Organisms sampled for population level research are typically assigned to species by morphological criteria. But if those criteria are limited to one sex or life stage, or the organisms come from a complex of closely related forms, the species assignments may misdirect analyses. The impact of such sampling can be assessed from the correspondence of genetic clusters, identified only from patterns of genetic variation, to the species identified using only phenotypic criteria. We undertook this protocol with the rock-dwelling mbuna cichlids of Lake Malawi, for which species within genera are usually identified by investigators using adult male coloration patterns. Given high local endemism of male color patterns, and considerable allele sharing among species, there persists considerable taxonomic uncertainty in these fishes. Over 700 individuals from a single transect were photographed, genotyped, and separately assigned: (1) to morphospecies using photographs; and (2) to genetic clusters using five widely used methods. Overall, the correspondence between clustering methods was strong for larger clusters, but methods varied widely in estimated number of clusters. The correspondence between morphospecies and genetic clusters was also strong for larger clusters, as well as some smaller clusters for some methods. These analyses generally affirm (1) adult male-limited sampling and (2) the taxonomic status of Lake Malawi mbuna, as the species in our study largely appear to be well-demarcated genetic entities. More generally, our analyses highlight the challenges for clustering methods when the number of populations is unknown, especially in cases of highly uneven sample sizes.

Figure 6 from: Dierickx K, Hanssens M, Rusuwa B, Snoeks J (2018) Trematocranus pachychilus, a new endemic cichlid from Lake Malawi (Teleostei, Cichlidae). ZooKeys 743: 153-166. https://doi.org/10.3897/zookeys.743.22814

Figure 6 Lower pharyngeal bones, dorsal view (left) and lateral view (right): A. Trematocranus pachychilus, paratype, MRAC 99-041-P-4782, 151.9 mm SL, Lake Malawi, Jafua Bay; B. T. microstoma, MRAC 99-041-P-4787, 143.7 mm SL; C. T. placodon, MRAC 99-041-P-4776, 153.8 mm SL. Scale bar: 5 mm.

Figure 5 from: Dierickx K, Hanssens M, Rusuwa B, Snoeks J (2018) Trematocranus pachychilus, a new endemic cichlid from Lake Malawi (Teleostei, Cichlidae). ZooKeys 743: 153-166. https://doi.org/10.3897/zookeys.743.22814

Figure 5 Photographs of preserved specimens: A Trematocranus pachychilus, holotype, MRAC 99-041-P-4781, adult male, 154.6 mm SL, Lake Malawi, Jafua Bay B T. microstoma, MRAC 99-041-P-4787, 143.7 mm SL, Lake Malawi, Mazinzi Bay C T. placodon, MRAC 99-041-P-4776, 153.8 mm SL, Lake Malawi, Jafua Bay D T. placodon, MRAC 99-041-P-4798, 149.3 mm SL, Lake Malawi, Senga Bay. Scale bar: 2 cm.

Figure 4 from: Dierickx K, Hanssens M, Rusuwa B, Snoeks J (2018) Trematocranus pachychilus, a new endemic cichlid from Lake Malawi (Teleostei, Cichlidae). ZooKeys 743: 153-166. https://doi.org/10.3897/zookeys.743.22814

Figure 4 Scatter plot of PC 1 against PC 2 for a principal component analysis of 11 counts of T. pachychilus and T. placodon (n=20). Trematocranus placodon: white square; Trematocranus pachychilus holotype: white circle; paratypes: grey circle.

Figure 1 from: Dierickx K, Hanssens M, Rusuwa B, Snoeks J (2018) Trematocranus pachychilus, a new endemic cichlid from Lake Malawi (Teleostei, Cichlidae). ZooKeys 743: 153-166. https://doi.org/10.3897/zookeys.743.22814

Figure 1 Scatter plot of PC 1 against PC 3 for a principal component analysis of 24 log-transformed measurements of T. pachychilus and T. microstoma (n = 17). Trematocranus microstoma: white triangle; Trematocranus pachychilus holotype: white circle; paratypes: grey circle.

Figure 3 from: Dierickx K, Hanssens M, Rusuwa B, Snoeks J (2018) Trematocranus pachychilus, a new endemic cichlid from Lake Malawi (Teleostei, Cichlidae). ZooKeys 743: 153-166. https://doi.org/10.3897/zookeys.743.22814

Figure 3 Scatter plot of PC 1 against PC 2 for a principal component analysis of 24 log-transformed measurements of T. pachychilus and T. placodon (n = 20). Trematocranus placodon: white square; Trematocranus pachychilus holotype: white circle; paratypes: grey circle.

Figure 2 from: Dierickx K, Hanssens M, Rusuwa B, Snoeks J (2018) Trematocranus pachychilus, a new endemic cichlid from Lake Malawi (Teleostei, Cichlidae). ZooKeys 743: 153-166. https://doi.org/10.3897/zookeys.743.22814

Figure 2 Scatter plot of PC 1 against PC 2 for a principal component analysis of eleven counts of T. pachychilus and T. microstoma (n = 17). Trematocranus microstoma: white triangle; Trematocranus pachychilus holotype: white circle; paratypes: grey circle.

publicApr 2019View details →

Data from: A population genetic assessment of taxonomic species: the case of Lake Malawi cichlid fishes

Open the record for dataset details and reuse information.

publicDec 2012View details →

Data from: Mitochondrial genome primers for Lake Malawi cichlids

Open the record for dataset details and reuse information.

publicJul 2018View details →

Data from: Evolutionary divergence in life history traits among populations of the Lake Malawi cichlid fish Astatotilapia calliptera

Open the record for dataset details and reuse information.